diff options
Diffstat (limited to 'drivers/w1/masters/matrox_w1.c')
| -rw-r--r-- | drivers/w1/masters/matrox_w1.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/drivers/w1/masters/matrox_w1.c b/drivers/w1/masters/matrox_w1.c new file mode 100644 index 000000000..ee716c715 --- /dev/null +++ b/drivers/w1/masters/matrox_w1.c @@ -0,0 +1,208 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * matrox_w1.c + * + * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> + */ + +#include <asm/types.h> +#include <linux/atomic.h> +#include <asm/io.h> + +#include <linux/delay.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/list.h> +#include <linux/interrupt.h> +#include <linux/spinlock.h> +#include <linux/timer.h> +#include <linux/slab.h> +#include <linux/pci_ids.h> +#include <linux/pci.h> + +#include <linux/w1.h> + +/* + * Matrox G400 DDC registers. + */ + +#define MATROX_G400_DDC_CLK (1<<4) +#define MATROX_G400_DDC_DATA (1<<1) + +#define MATROX_BASE 0x3C00 +#define MATROX_STATUS 0x1e14 + +#define MATROX_PORT_INDEX_OFFSET 0x00 +#define MATROX_PORT_DATA_OFFSET 0x0A + +#define MATROX_GET_CONTROL 0x2A +#define MATROX_GET_DATA 0x2B +#define MATROX_CURSOR_CTL 0x06 + +struct matrox_device +{ + void __iomem *base_addr; + void __iomem *port_index; + void __iomem *port_data; + u8 data_mask; + + unsigned long phys_addr; + void __iomem *virt_addr; + unsigned long found; + + struct w1_bus_master *bus_master; +}; + +/* + * These functions read and write DDC Data bit. + * + * Using tristate pins, since i can't find any open-drain pin in whole motherboard. + * Unfortunately we can't connect to Intel's 82801xx IO controller + * since we don't know motherboard schema, which has pretty unused(may be not) GPIO. + * + * I've heard that PIIX also has open drain pin. + * + * Port mapping. + */ +static __inline__ u8 matrox_w1_read_reg(struct matrox_device *dev, u8 reg) +{ + u8 ret; + + writeb(reg, dev->port_index); + ret = readb(dev->port_data); + barrier(); + + return ret; +} + +static __inline__ void matrox_w1_write_reg(struct matrox_device *dev, u8 reg, u8 val) +{ + writeb(reg, dev->port_index); + writeb(val, dev->port_data); + wmb(); +} + +static void matrox_w1_write_ddc_bit(void *data, u8 bit) +{ + u8 ret; + struct matrox_device *dev = data; + + if (bit) + bit = 0; + else + bit = dev->data_mask; + + ret = matrox_w1_read_reg(dev, MATROX_GET_CONTROL); + matrox_w1_write_reg(dev, MATROX_GET_CONTROL, ((ret & ~dev->data_mask) | bit)); + matrox_w1_write_reg(dev, MATROX_GET_DATA, 0x00); +} + +static u8 matrox_w1_read_ddc_bit(void *data) +{ + u8 ret; + struct matrox_device *dev = data; + + ret = matrox_w1_read_reg(dev, MATROX_GET_DATA); + + return ret; +} + +static void matrox_w1_hw_init(struct matrox_device *dev) +{ + matrox_w1_write_reg(dev, MATROX_GET_DATA, 0xFF); + matrox_w1_write_reg(dev, MATROX_GET_CONTROL, 0x00); +} + +static int matrox_w1_probe(struct pci_dev *pdev, const struct pci_device_id *ent) +{ + struct matrox_device *dev; + int err; + + if (pdev->vendor != PCI_VENDOR_ID_MATROX || pdev->device != PCI_DEVICE_ID_MATROX_G400) + return -ENODEV; + + dev = kzalloc(sizeof(struct matrox_device) + + sizeof(struct w1_bus_master), GFP_KERNEL); + if (!dev) { + dev_err(&pdev->dev, + "%s: Failed to create new matrox_device object.\n", + __func__); + return -ENOMEM; + } + + + dev->bus_master = (struct w1_bus_master *)(dev + 1); + + /* + * True for G400, for some other we need resource 0, see drivers/video/matrox/matroxfb_base.c + */ + + dev->phys_addr = pci_resource_start(pdev, 1); + + dev->virt_addr = ioremap(dev->phys_addr, 16384); + if (!dev->virt_addr) { + dev_err(&pdev->dev, "%s: failed to ioremap(0x%lx, %d).\n", + __func__, dev->phys_addr, 16384); + err = -EIO; + goto err_out_free_device; + } + + dev->base_addr = dev->virt_addr + MATROX_BASE; + dev->port_index = dev->base_addr + MATROX_PORT_INDEX_OFFSET; + dev->port_data = dev->base_addr + MATROX_PORT_DATA_OFFSET; + dev->data_mask = (MATROX_G400_DDC_DATA); + + matrox_w1_hw_init(dev); + + dev->bus_master->data = dev; + dev->bus_master->read_bit = &matrox_w1_read_ddc_bit; + dev->bus_master->write_bit = &matrox_w1_write_ddc_bit; + + err = w1_add_master_device(dev->bus_master); + if (err) + goto err_out_free_device; + + pci_set_drvdata(pdev, dev); + + dev->found = 1; + + dev_info(&pdev->dev, "Matrox G400 GPIO transport layer for 1-wire.\n"); + + return 0; + +err_out_free_device: + if (dev->virt_addr) + iounmap(dev->virt_addr); + kfree(dev); + + return err; +} + +static void matrox_w1_remove(struct pci_dev *pdev) +{ + struct matrox_device *dev = pci_get_drvdata(pdev); + + if (dev->found) { + w1_remove_master_device(dev->bus_master); + iounmap(dev->virt_addr); + } + kfree(dev); +} + +static struct pci_device_id matrox_w1_tbl[] = { + { PCI_DEVICE(PCI_VENDOR_ID_MATROX, PCI_DEVICE_ID_MATROX_G400) }, + { }, +}; +MODULE_DEVICE_TABLE(pci, matrox_w1_tbl); + +static struct pci_driver matrox_w1_pci_driver = { + .name = "matrox_w1", + .id_table = matrox_w1_tbl, + .probe = matrox_w1_probe, + .remove = matrox_w1_remove, +}; +module_pci_driver(matrox_w1_pci_driver); + +MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>"); +MODULE_DESCRIPTION("Driver for transport(Dallas 1-wire protocol) over VGA DDC(matrox gpio)."); +MODULE_LICENSE("GPL"); |